We framed each door/window on either side with a vertical then on the top piece with a horizontal 1 x Above the we added a horizontal simple cove moulding strip (the rounded part) and on top of that, a horizontal 1 x 2 firring strip.
*add this to build up baseboards in house - To make your baseboard more dramatic, add small pieces of trim to the top of existing baseboard, add a few inches and add another piece of moulding. Paint the wall and trim white.
Love this window but NO PIVOT WINDOWS! Dumbest things ever made! Make a farmhouse window - add window trim to beef up a plain window with no miter cuts in sight! Made from a plain, modern window via www.